Given its current ubiquity in banking and other services, digital payments should be accessible to all, but neurodiverse populations encounter barriers often understudied in research and practice. A greater understanding of user needs across the neurodivergent spectrum will thus improve universal access. To characterize the cognitive accessibility of digital payments, this literature review examines 30 scholarly publications, nuancing the challenges of online banking for older adults and people with neurodiverse needs. Our findings uncover a range of potential design and support strategies, including simplifying interfaces with diversified cues, raising designer awareness and participant involvement, extending thirdparty support, and leveraging new technological aids. We further discuss implications for digital currency design through support for user agency, collaborative payments, contextualized inclusive approaches, and AI-powered accessible design, hopefully inspiring future research on improving web accessibility. CCS CONCEPTS• Human-centered computing → Accessibility.